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Electric Lorentz

In order to illustrate some of the basic aspects of the nonlinear optical response of materials, we first discuss the anliannonic oscillator model. This treatment may be viewed as the extension of the classical Lorentz model of the response of an atom or molecule to include nonlinear effects. In such models, the medium is treated as a collection of electrons bound about ion cores. Under the influence of the electric field associated with an optical wave, the ion cores move in the direction of the applied field, while the electrons are displaced in the opposite direction. These motions induce an oscillating dipole moment, which then couples back to the radiation fields. Since the ions are significantly more massive than the electrons, their motion is of secondary importance for optical frequencies and is neglected. [Pg.1266]

The collision terms may be simplified by using the condition that mjM is very small this leads to the Lorentz approximation. If there were no electric field, the equilibrium situation would be one in which the mean kinetic energy of the electrons would be equal to that of the... [Pg.47]

Loeb, AL Overbeek, JTG Wiersema, PH, The Electrical Double Layer Around a Spherical Colloid Particle, Computation of the Potential, Charge Density, and Free Energy of the Electrical Double Layer Around a sperical Colloid Particle M.I.T. Press Cambridge, MA, 1961. Lorentz, HA, Wied, Ann. 11, 70, 1880. [Pg.615]

A filter that combines both a magnetic and electric field is the so-called Wien filter (or velocity filter). In this case, charged ions pass through a region characterized by uniform magnetic and electric fields at right angles to each other and to the direction of incident ions only those particles for which the module of the Lorentz... [Pg.464]

If there is also an electric field present, the electric force qE must be taken into account as well. The complete force equation for a charged mass point, also known as the Lorentz force, is... [Pg.129]

Let us now analyze the interaction of a light wave with our collection of oscillators at frequency two- In this case, the general motion of a valence electron bound to a nucleus is a damped oscillator, which is forced by the oscillating electric field of the light wave. This atomic oscillator is called a Lorentz oscillator. The motion of such a valence electron is then described by the following differential equation ... [Pg.117]

Finally, a special type of primary bond known as a metallic bond is found in an assembly of homonuclear atoms, such as copper or sodium. Here the bonding electrons become decentralized and are shared by the core of positive nuclei. Metallic bonds occur when elements of low electronegativity (usually found in the lower left region of the periodic table) bond with each other to form a class of materials we call metals. Metals tend to have common characteristics such as ductility, luster, and high thermal and electrical conductivity. All of these characteristics can to some degree be accounted for by the nature of the metallic bond. The model of a metallic bond, first proposed by Lorentz, consists of an assembly of positively charged ion cores surrounded by free electrons or an electron gas. We will see later on, when we... [Pg.11]

The return to equilibrium of a polarized region is quite different in the Debye and Lorentz models. Suppose that a material composed of Lorentz oscillators is electrically polarized and the static electric field is suddenly removed. The charges equilibrate by executing damped harmonic motion about their equilibrium positions. This can be seen by setting the right side of (9.3) equal to zero and solving the homogeneous differential equation with the initial conditions x = x0 and x = 0 at t = 0 the result is the damped harmonic oscillator equation ... [Pg.260]

The present chapter is devoted mainly to one of these new theories, in particular to its possible applications to photon physics and optics. This theory is based on the hypothesis of a nonzero divergence of the electric field in vacuo, in combination with the condition of Lorentz invariance. The nonzero electric field divergence, with an associated space-charge current density, introduces an extra degree of freedom that leads to new possible states of the electromagnetic field. This concept originated from some ideas by the author in the late 1960s, the first of which was published in a series of separate papers [10,12], and later in more complete forms and in reviews [13-20]. [Pg.3]

The introduction of the current density (3) in 3-space is, in fact, less intuitive than what could appear at first glance. As soon as the charge density (4) is permitted to exist as the result of a nonzero electric field divergence, the Lorentz invariance of a 4-current (7) with the time part namely requires the associated space part to adopt the form (3), that is, by necessity. [Pg.7]

The Lorentz transformation is further applied to the electric and magnetic fields, which become... [Pg.34]

The Maxwell-Heaviside theory of electrodynamics has no explanation for the Sagnac effect [4] because its phase is invariant under 7 as argued already, and because the equations are invariant to rotation in the vacuum. The d Alembert wave equation of U(l) electrodynamics is also 7 -invariant. One of the most telling pieces of evidence against the validity of the U(l) electrodynamics was given experimentally by Pegram [54] who discovered a little known [4] cross-relation between magnetic and electric fields in the vacuum that is denied by Lorentz transformation. [Pg.119]

The so-called Aharonov-Bohm effect is observed with another experimental setup. A solenoid is placed immediately after the plate, between the slits, and its axis is parallel to the slits, and therefore normal to the beam trajectory beam. If the solenoid is long enough, the magnetic field remains confined in it as a consequence, the magnetic field is shown to have a null value in the region crossed by electrons beamed on either sides of the solenoid. The Lorentz force exerted on the electrons is expected to be null in the absence of any external electrical field. [Pg.597]

Since the present standard U(l) electrodynamics model forbids electrical power systems with COP > 1.0, my colleagues and I also studied the derivation of that model, which is recognized to contain flaws due to its > 136-year-old basis. We particularly examined how it developed, how it was changed, and how we came to have the Lorentz-regauged Maxwell-Heaviside equations model ubiquitously used today, particularly with respect to the design, manufacture, and use of electrical power systems. [Pg.702]

Later H. A. Lorentz [15],5 apparently unaware of Lorenz 1867 work, independently regauged the Maxwell-Heaviside equations so that they represented a system that was in equilibrium with its active environment. This indeed simplified the mathematics, thus minimizing numerical methods. However, it also discarded all electrical windmills in a free wind —so to speak—and left only those electrical windmills in a large sealed room where there was never any net free wind. [Pg.703]


See other pages where Electric Lorentz is mentioned: [Pg.531]    [Pg.542]    [Pg.531]    [Pg.542]    [Pg.1311]    [Pg.42]    [Pg.414]    [Pg.428]    [Pg.131]    [Pg.277]    [Pg.787]    [Pg.21]    [Pg.581]    [Pg.455]    [Pg.116]    [Pg.127]    [Pg.44]    [Pg.166]    [Pg.60]    [Pg.160]    [Pg.228]    [Pg.259]    [Pg.260]    [Pg.73]    [Pg.74]    [Pg.21]    [Pg.37]    [Pg.48]    [Pg.642]    [Pg.702]    [Pg.703]    [Pg.704]    [Pg.707]    [Pg.716]    [Pg.128]    [Pg.8]   
See also in sourсe #XX -- [ Pg.332 ]




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